1. Field of Invention
The present invention relates to devices and methods for repairing leaks in vehicle heater core structures. More particularly, the present invention relates to such devices and methods which do not require removal of the heater core from its attached position within the vehicle.
2. Prior Art
A conventional heating and cooling system in a combustion powered motor vehicle utilizes a heating core as a heat transfer element. This heating core comprises a coiled tube which is coupled into the fluid circulating network of the cooling system of the vehicle. As water/coolant within this cooling system is heated by the combustion engine, a water pump is activated and circulates the water between the radiator and the block of the engine. When the heating system for the vehicle passenger section is activated, the heated fluid is transferred through the heater core, which is usually positioned near the fire wall of the vehicle, considerably removed from the radiator and associated connect lines. The separated relationship of the heater core from the cooling system and its positioning within the vehicle structure create numerous problems upon occurrence of a leak in one or more of the coils of the heater core. Current procedure for repair of such a leak involves introduction of a fluid, sealing compound into the flow line near the radiator and pumping of this solution into the heater core. Ideally, the sealing solution flows through the heater core at the location of the leak, to form a bonded plug which blocks the leak opening. Unfortunately, various forms of deposits and residue accumulate within the heater core which may inhibit effective sealing by the stop-leak compound. Efforts to flush out this residue are often not effective because the heater core is so far removed from entry of the flush solution that effective turbulent action is lost and scaling off of the protective residue coating is minimal.
If repair requires a thorough flushing and effective application of a leak sealing compound, removal of the heater core from the vehicle is typically required with direct flushing and treatment by a fluid pumping system. This service involves considerable expense, primarily because of the substantial labor required to access the heater core and remove it from its "buried" location within the vehicle structure. In fact, general consensus favors replacement of the heater core with a new heater core rather than repair in view of the referenced high cost of labor.
Therefore, a vehicle owner who is faced with the problem of a leaking heater core has only two effective options. First, the owner can attempt to cure the leakage by pumping sealant compound through the coolant system by accessing tubing coupled near the radiator. This not only poses the difficulty of getting the sealing compound through the coolant system to the heater core in sufficient concentration, but also exposes the water pump and other areas within the coolant fluid circuit to possible detrimental effects of the sealing compound. The effectiveness of such repair has already been placed in question in view of the difficulty of developing an effective flush technique for reaching the heater core to expose core material to sealing action of the compound.
The remaining option is to incur the high expense of removing the heater core so that direct repair can be effectively made. At this point of considerable expense, most repairmen would advise replacement of the core with a new core element because of likelihood of occurrence of new leak locations, with the renewed requirement of heavy labor expense to again pull the heater core element from its difficult location.
Accordingly, what is needed is a method or apparatus for enabling effective and inexpensive repair of the heater core without the need of removing the structure from its location within the vehicle.